On the campaign trail, Senators Barack Obama and John McCain meet for their second debate tomorrow night, a town-hall event in Nashville, Tennessee. The McCain campaign has begun what it calls a new phase of intensified attacks on Obama. On Saturday, Republican vice-presidential nominee Sarah Palin raised Obama’s alleged links to Bill Ayers, a former member of the Vietnam-era militant group the Weather Underground.

Alaska Gov. Sarah Palin: “One of his [Obama’s] earliest supporters is a man who, according to the New York Times, was a domestic terrorist and part of a group — part of a group that, quote, 'launched a campaign of bombings that would target the Pentagon and the US Capitol.'”

Ayers today is a tenured professor at the University of Illinois at Chicago. In a statement, Chicago Mayor Richard Daley called him “a valued member of the Chicago community” who has “worked with me in shaping our now nationally renowned school reform program.” It’s said Ayers and Obama have few ties beyond living in the same Chicago neighborhood and having once served together on the board of two nonprofits. Ayers also hosted a fundraiser for Obama when he ran for the State Senate. In North Carolina, Obama dismissed the allegations as a desperate political ploy.

Sen. Barack Obama: “Senator McCain and his operatives are gambling that they can distract you with smears rather than talk to you about substance. They’d rather tear our campaign down than lift this country up. That’s what you do when you’re out of touch, out of ideas, and running out of time.”